Magma can partially crystallize at depth and then rise to shallow depths where the remaining magma solidifies. the early-formed crystals are and the texture is . in very large crystals can grow, forming . magma that cools in has a relatively short time to cool and so forms , but not volcanic glass. in , magma cools at a slow rate, allowing the formation of .

The heater element of a 120 v toaster is a 5.4 m length of nichrome wire, whose diameter is 0.48 mm. the resistivity of nichrome at the operating temperature of the toaster is 1.3 × 10-6 ω·m. the toaster is operated at a voltage of 120 v. (a) what is the power drawn by the toaster? (b) if the cost of electricity is 12 ¢ per kilowatt-hour, and it takes 2 minutes to toast bread, how much does it cost for toasted bread? (c) when the heater element is at room temperature, is the resistivity in the nichrome wire greater than, less than, or equal to it’s resistivity when at operating temperature? explain.